This NASA Discovery mission is to be launched in June 2008 and will search for Earth-size and smaller planets. Launch was originally scheduled in 2007 but delayed by 8 months due to "funding constraints".

Title: The Effect of the Transit of Venus on ACRIM's Total Solar Irradiance Measurements: Implications for Transit Studies of Extrasolar Planets

Authors: G. Schneider, J. M. Pasachoff and R. C. Willson

Comments: Accepted to ApJ 8 Dec 2005; 14 pages of text, 8 figures, 1 table\\ We used the 8 June 2004 transit of Venus (ToV) as a surrogate to testobserving methods, strategies and techniques that are being contemplated forfuture space missions to detect and characterize extrasolar terrestrial planets(ETPs) as they transit their host stars, notably NASA's Kepler mission plannedfor 2008. As an analog to "Kepler-like" photometric transit observations, weobtained (spatially unresolved) radiometric observations with the ACRIM 3instrument on ACRIMSAT to follow the effect of the ToV on the total solarirradiance (TSI). Contemporaneous high-resolution broadband imagery with NASA'sTRACE spacecraft provided, directly, measures of the stellar (solar)astrophysical noise that can intrinsically limit such transit observations.During the ~ 5.5 h transit, the planet's angular diameter was approximately1/32 the solar diameter, thus covering ~ 0.1 of the stellar surface. With ourACRIM 3 data, we measure temporal changes in TSI with a 1 sigma per sample(unbinned) uncertainty of approximately 100 mW m^-2 (0.007%). A diminution inTSI of ~ 1.4 W m^-2 (~ 0.1%, closely corresponding to the geometricallyocculted area of the photosphere) was measured at mid-transit compared with amean pre/post transit TSI of ~ 1365.9 W m^-2. These observations serve as asurrogate to future photometric observations of ETPs such as Kepler willdeliver. Detailed analysis of the ToV, a rare event within our own solarsystem, with time-resolved radiometry augmented with high-resolution imageryprovides a useful analogue for investigating the detectability andcharacterization of ETPs from observations that are anticipated in the nearfuture.

"After having some business dealings with men, I am occasionally chagrined, and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

We examined which exo-systems contain moons that may be detected in transit. We numerically modeled transit light curves of Earth-like and giant planets that cointain moons with 0.005--0.4 Earth-mass. The orbital parameters were randomly selected, but the entire system fulfilled Hill-stability. We conclude that the timing effect is caused by two scenarios: the motion of the planet and the moon around the barycenter. Which one dominates depends on the parameters of the system.

Already planned missions (Kepler, COROT) may be able to detect the moon in transiting extrasolar Earth-Moon-like systems with a 20% probability. From our sample of 500 free-designed systems, 8 could be detected with the photometric accuracy of 0.1 mmag and a 1 minute sampling, and one contains a stony planet. With ten times better accuracy, 51 detections are expected. All such systems orbit far from the central star, with the orbital periods at least 200 and 10 days for the planet and the moon, while they contain K- and M-dwarf stars.

Finally we estimate that a few number of real detections can be expected by the end of the COROT and the Kepler missions.

"After having some business dealings with men, I am occasionally chagrined, and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

One of the biggest cosmic dust storms of the past 80 million years left a blanket of material on Earth after an asteroid in space broke apart, researchers said today.

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"After having some business dealings with men, I am occasionally chagrined, and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? We've heard second hand reports via Bruce that the budget has been busted, but that NASA will keep the money flowing. But has the project moved much lately?

According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? We've heard second hand reports via Bruce that the budget has been busted, but that NASA will keep the money flowing. But has the project moved much lately?

I am interested in it as wellWell I downloaded the NASA's budget document and it seems that Kepler is going to be launched...unless I interpret the language in wrong way:http://www.nasa.gov/pdf/142458main_FY07_budget_full.pdfBut the ATLO you speak about is written in the document as only to be conducted. I am really interested and hope somebody could share a light on this.

Latest news is that the launch is currently set for mid-2008. They seem determined not to cancel it, although there may be further delays. (Once again, we have dramatic evidence of the extent to which Discovery proposers are tempted to understate their mission's cost and then try to persuade NASA to go along with it anyway. I hope Dawn hasn't set a disastrous precedent in this, or the Solar System Groupies may have shot themselves badly in the foot by demanding that it not be cancelled.)

Looks like a great mission, we've got loads of exoplanet missions Corot, Kepler, TPF and Darwin ( If the budget stays good then NASA have some great exoplanet mission plans - unless of course NASA continues to hacking bits off TPF until there's nothing left )

According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? But has the project moved much lately?

Today, I noticed that the Kepler web site schedule has been updated. Launch has been slipped by 4 months due to fiscal matters, and is now scheduled for October 2008. In addition, the Critical Design Review is scheduled for this month, April 2006.

In addition, Kepler will now feature a fixed High Gain antenna, instead of featuring a gimbal. According to the website, this was done to reduce risk, cost and complexity. However, this means that Kepler will miss 1 day's worth of observing per month.

This is targeted at those with some familiarity with sources of Astronomical images. I am including links to the planned Field of View (FOV) for the Kepler mission. The first page links to a brief description of the FOV's location, while the second link is a more detailed pdf of the FOV itself.

What I am looking for would be telescope images of the FOV, showing the star fields in some detail. I have searched the Kepler web site, but there are no such telescopic photos there. I think that is a shame. Kepler's mission involves searching for extra-solar planetary transits using a fancy photometer. The resulting light curves will be great to analyze, but the public (including me) will want to see just what Kepler was looking at.

I think that a mosaic of images of the target FOV Milky Way star field should be magnificent. To me, such public outreach should be something that the Kepler team would want to pursue.

Are there known transiting exoplanets in that piece of sky for cross-checking purposes?

I know two exo-planets have been discovered by the use of the transit method. However, the only planet that could be used to calibrate or test such technologies at the current time is Venus. Scientists used the June 8, 2004 transit to test alot of devices and technologies that Kepler and future missions will use.

The most important one was done by ACRIM which showed a orbiting spacecraft CAN detect a minute drop (about 0.1%) in a parent star's (the Sun!) light reaching a detector.

Good news though: There will be another transit on June 6, 2012. I bet this will be used as well!

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I call heaven and earth to witness against you this day, that I have set before thee life and death, the blessing and the curse; therefore choose life, that thou mayest live, thou and thy seed.

The most important one was done by ACRIM which showed a orbiting spacecraft CAN detect a minute drop (about 0.1%) in a parent star's (the Sun!) light reaching a detector.

Good news though: There will be another transit on June 6, 2012. I bet this will be used as well!

It seems to me that many more opportunities happen than this. We need only look at the light curve of medium to large asteroids as the Earth, or Venus, or Mars, or Jupiter transit the Sun from their locations. There must be dozens of such events per year. More if you want to look at smaller objects.

This is targeted at those with some familiarity with sources of Astronomical images. I am including links to the planned Field of View (FOV) for the Kepler mission. The first page links to a brief description of the FOV's location, while the second link is a more detailed pdf of the FOV itself.

http://kepler.nasa.gov/sci/basis/images/New_FOV_6m.pdf What I am looking for would be telescope images of the FOV, showing the star fields in some detail. I have searched the Kepler web site, but there are no such telescopic photos there. I think that is a shame. Kepler's mission involves searching for extra-solar planetary transits using a fancy photometer. The resulting light curves will be great to analyze, but the public (including me) will want to see just what Kepler was looking at.

I think that a mosaic of images of the target FOV Milky Way star field should be magnificent. To me, such public outreach should be something that the Kepler team would want to pursue. Another Phil

I believe that they do intend to get a lot of data on star variability as a fringe benefit from the Kepler mission -- just as ESA's cancelled Eddington mission would have done the same two things, but in reverse order of priority.

By the way, one selling point for the proposed "Joint Dark Energy Mission" that NASA and the Dept. of Energy were planning to team up on as the first "Beyond Einstein" mission -- although those have been put on indefinite hold due to the serious funding problems in NASA's Astrophysics Division -- was that, by adding just $100 million to its total cost, it could follow up its initial measurements of very distant supernovas with a very extensive microlensing census of planets in one of the Magellanic Clouds.

Kepler will be staring at this FOV for 4 years, looking for transits. In this FOV, there are about 200,000 stars, half of which will meet the criteria for planetary search (single, non-variable, etc.).

Therefore, Kepler will be sorting through the brightness stability of about 100,000 stars. I think that it would add immensely to one's appreciation of the magnitude of Kepler's mission if there were actual images of the galactic star fields inserted into the FOV above.

In fact, it would be helpful to have high-res digital images of each of the 21 sub-fields (each of these sub-fields will be covered by one of Kepler's CCD's).

Does anyone have access to a good source of Milky Way digital imagery, especially of the area near Cygnus, shown above?

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